Effect of prolonged glucose infusion into fetal sheep on body growth, fat deposition and gestation length.
Eleven Merino sheep fetuses were supplemented with glucose by direct continuous intravenous infusion of 50% dextrose into the fetus from day 115 of gestation until spontaneous delivery. Infusion rates of 15 or 25 g/day per kg were used and equivalent volumes of saline were infused into 11 control fetuses. Infusion periods approximated 27 days in both groups. Fetal plasma glucose concentrations were significantly (P less than 0.001) elevated throughout glucose infusion and resulted in variable but consistently higher plasma insulin concentrations in the glucose than in the saline-infused fetuses. Glucose-infused fetuses were significantly heavier than controls (mean +/- SEM; 3.86 +/- 0.16 vs 3.28 +/- 0.24 kg, P less than 0.05) and body fat depots (in g/kg body wt.) were larger in glucose-infused than control fetuses (9.91 +/- 0.65 vs 6.73 +/- 0.37, P less than 0.005, for internal brown fat depots; 1.25 +/- 0.44 vs 0.27 + 0.13, P less than 0.05, for subcutaneous white adipose tissue). The results indicate that growth and lipid deposition in the sheep fetus are responsive to increased glucose supply, an effect which may be mediated through the actions of insulin. Mean gestation length was 146.60 +/- 1.45 days for controls and 144.18 +/- 1.23 days for glucose-infused animals (normal term 150 days).
Stevens
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D
CSIRO, Division of Animal Production, Blacktown, NSW, Australia.
Alexander
G
G
Bell
A W
AW
D000273:Adipose Tissue / Q000378:metabolism*; D000704:Analysis of Variance; D000818:Animals; D001724:Birth Weight / Q000187:drug effects*; D001786:Blood Glucose / Q000032:analysis; D005314:Embryonic and Fetal Development / Q000187:drug effects*; D005260:Female; D005312:Fetal Blood / Q000737:chemistry; D005865:Gestational Age; D005947:Glucose / Q000008:administration & dosage / Q000494:pharmacology*; D007262:Infusions, Intravenous / Q000662:veterinary; D007328:Insulin / Q000097:blood; D007773:Lactates / Q000097:blood; D009994:Osmolar Concentration; D011247:Pregnancy; D012756:Sheep / Q000196:embryology*
D001786:Blood Glucose; D007328:Insulin; D007773:Lactates; D005947:Glucose